Q&A: A magnolia in the Seattle area, sure, but an olive tree?

Q: When I visited your garden on the recent Northwest Horticultural Society tour, I noticed a tree near your patio with white flowers that face downward. What tree is that?

A: The tree you saw growing over my patio is Magnolia sieboldii, commonly known as the Oyama magnolia. This deciduous tree is hardy to about mimus10 degrees and can grow anywhere from 15 to 30 feet tall and wide, although it can be kept smaller with pruning.

The lemon-scented, nodding, porcelain-white flowers contrast beautifully with a cone of crimson stamens located in the center of the blossom. The flowers are produced in abundance in late spring, bloom sporadically during summer, then end the season with a prolific display once again in fall.

M. sieboldii requires a sunny location, in moist, well-drained soil to thrive and bloom. Fortunately, if you lack a sunny location, you’re not out of luck. Magnolia wilsonii grows to about the same size and produces very similar nodding red-centered flowers. The main difference is that M. wilsonii thrives and blooms prolifically in shade.

Both of these magnolias are occasionally available at quality nurseries, or you can order them online from mail-order nurseries.

Q: I recently saw a beautiful 5-foot Arbequina olive tree for sale at my local nursery. Will an olive tree survive in the Seattle area, and if so, will it produce edible fruit?

A: Nothing adds a touch of Tuscany better than planting an Arbequina olive in your garden. I’ve had one growing at my home for at least 10 years. These trees were brought to Spain from the Middle East in the 17th century and are among the most productive olive trees worldwide.

They’ll grow quite well here, but these trees are only hardy to around 15 degrees, so whether it will survive in your garden depends on where you live. If you reside where it doesn’t tend to get excessively cold, it’s worth a try. Even if the tree gets somewhat maimed in a cold winter, it may survive.

These sun-loving, drought-tolerant trees typically grow to about 20 feet tall and wide. The trunk and branches take on a gnarled, rustic look as they age. The silvery undersides of the evergreen leaves are particularly attractive.

In the Puget Sound region, these self-fertile trees can produce heavy crops of high-quality fruit. The fruit will turn black, showing that it has ripened to maturity, but that only happens in summers with plenty of hot, sunny weather, and if the birds don’t get them first.

You can’t just eat the fruit right off the tree, by the way. You have to pickle it first. Start by placing your clean olives in cold water and change the water each day for 10 days. Then make a brine solution adding one cup of noniodized salt to each gallon of water, making sure the solution covers the olives.

Change this solution weekly for four weeks. Then leave the fruit in the brine until it’s ready to eat in two or three months. Taste weekly to determine when the olives are ready to eat.